Differential pressure sensors are crucial for preserving energy and guaranteeing that HVAC systems operate to their full potential. Numerous air handling systems and applications employ sensors to measure air pressure. Here is an illustration of a few of the more popular ones:
Image Credit: Superior Sensor Technology
HV Series Differential Pressure Sensors
The HV Series' broad dynamic range and fewer sensor variations are needed to meet the rigorous functional requirements of the HVAC market. Multiple pressure ranges can be provided in a single package.
With its steady zero point and extremely low noise floor, the HV provides the highest accuracy, longest-lasting stability, and lowest error rates when measuring dry air and non-aggressive gas pressure. Starting with pressure ranges as low as 25 pascals, exclusive multi-range technology allows the HV Series to accommodate up to eight pressure ranges in a single device.
The HV Series, with a warm-up period of only a few minutes and power-on time, can greatly benefit time-critical installation applications.
Source: Superior Sensor Technology
HV Series – Differential Pressure Sensors
Features
- Dual sensors that are highly integrated with ADC and DSP
- Ranges of selectable pressure are ±0.1 to ±60 in H2O
- Integrated Notch Filter at 50/60 Hz
- Variable bandwidth filter with a range of 0.1 Hz to 10 Hz
- Exceptionally good accuracy ±0.1% of the chosen range
- Stability throughout the long run ±0.1% of FSS in the first year
- Advanced digital filtering (Optional)
- Closed-loop integration (optional)
- Temperature-regulated between 0 °C and 50 °C
- Provide voltage correction
- Completely integrated compensation math with SPI and I2C interface standards
Image Credit: Superior Sensor Technology
Engineering Design Resources
90° Port Adapters
Depending on how the product is designed, customers might need to have the ports facing down instead of up. Plugging into the two ports of pressure sensors, Superior provides incredibly dependable and high-quality adapters that simplify installation. Users can stop worrying about z-height with the 90° adapters.
Both with and without o-rings, 90° adapters are available:
- KP-RAR: without o-rings
- KP-ROR: with o-rings
Packs of 50 and 1000 adapters are available for purchase.
Image Credit: Superior Sensor Technology
Recommended NimbleSense Features for HV Series
Multi-Range Technology
Across the HV Series, a single device can handle up to eight distinct pressure ranges, ranging from 25 Pa (0.1" H2O) to 15 kPa (60" H2O). Each range is factory-calibrated and tailored to maintain a constant total error band, accuracy, and stability.
This eliminates the intricacy and difficulties associated with using several sensors. Using a Multi-Range part simplifies the design and production process by eliminating the need to find, buy, and integrate many parts.
Implementing the same component in all designs is easier and more efficient, and it is convenient to regulate pressure adjustments with a single software command. Multi-range gives industrial processes the simplicity and added value of a single inventory item. In conclusion, both design and manufacturing teams may see multi-range benefits.
Benefits of Multi-Range technology include:
- The pressure range can be adjusted with design freedom throughout the development cycle.
- Streamlined product design by replacing up to eight separate sensors with a single sensor
- The capacity to swiftly create product variations at various pressure points without modifying the hardware architecture
- Larger purchases of the same commodity to achieve more significant economies of scale.
- Streamlined sensor calibration results in lower manufacturing costs and complexity.
- Reducing sensor inventory expenses and product obsolescence by up to eight times lets producers create fewer product variations, drastically reducing the amount of working capital and inventory needed.
Image Credit: Superior Sensor Technology
Closed-Loop Control
Closed-loop control improves the establishment and maintenance of flow rates by directly managing motors, valves, and actuators to regulate pressure. Superior offers the possibility of incorporating this functionality into the sensor, enabling more effective flow rate management and goal maintenance.
Loop delays in electrical circuits can be significantly reduced by up to 100 times, thanks to Superior's integrated closed-loop control design. This technique eliminates the need to create an intricate, external control loop system, resulting in more dependable, efficient, and affordable products.
It is impossible to exaggerate the advantages of integrated closed-loop control, particularly in the context of medical respiratory devices like CPAP, HVAC systems, unmanned aerial vehicles, and air quality measurement products.
The diagram below shows a block configuration for installing an excellent closed-loop control system for an air quality application. Keeping the airflow through the viewing window constant and preset is crucial for effective air quality monitoring.
Image Credit: Superior Sensor Technology
The differential pressure across the venturi is a clear indicator of the flow entering the viewing window. The differential pressure sensor automatically modifies the pump drive, up or down, to maintain the targeted differential pressure and an even airflow into the viewing window by setting a target pressure level across the venturi.
Combining the company's unique noise filtering technology with the NimbleSense closed-loop circuit successfully reduced loop latency by over 100 times.
Benefits of the Integrated Closed-Loop Control include:
- Reduce loop delays significantly to increase the product's accuracy and responsiveness.
- Eliminate discrete parts to increase the product's dependability.
- Cut down on the total cost of the system.
- Cut down on system heat and power.
- Reduce complexity in product design and expedite time to market
Image Credit: Superior Sensor Technology
Advanced Digital Filtering
Before crucial noise from blowers, fans, or other dry air/gas sources reaches the pressure-sensing subsystem, Superior's state-of-the-art digital filter, a multi-order filter, eliminates it using sophisticated filtering capabilities at the front end of the subsystem.
This is made possible by NimbleSense's sophisticated filtering capacity, which filters out mechanical noise from sensors before it can be interpreted as an error signal that could impair system performance.
In client deployments, the sensor has dramatically improved the SNR of the sensor output by reducing sensor-induced noise by over ten times, replacing a competing component. In extremely low-pressure situations, this improvement is even more significant.
This feature provides far superior noise reduction and removes the need to develop an external filtering system, resulting in more effective, dependable, and affordable products. It does this by incorporating both standard and optional digital filters.
The sophisticated digital filtering is adjusted to perfection for every application, guaranteeing that noise from mixed sampling is well below the noise level. Eliminating mechanical noise optimizes the system's overall performance.
Here is an illustration of a 4th-order FIR filter created especially to remove pump noise above 50 Hz or a noise level equal to the signal under observation. The graphs display the results of Superior's sophisticated digital filter.
Benefits of the Advanced Digital Filtering Technology include:
- A significant reduction in system noise of at least ten times is crucial in applications with extremely low pressure.
- An improvement of 100× to 1000× for noisy systems
- Remove noise sources like fans and blowers before noises enter the pressure-sensing sub-system.
- Use an integrated strategy to streamline product design.
- Eliminate the need to create an external filtering system, accelerating time to market.
Image Credit: Superior Sensor Technology
50/60 Hz Notch Filter
Despite Superior's pressure sensors' extraordinarily low noise floor, power line interference may be detectable during readings. That noise is, however, substantially suppressed by the included 50 Hz/60 Hz notch filter.
Consequently, consumers can continue to benefit from a pressure sensor's ultra-low noise floor without any outside disturbance. Furthermore, the smooth integration of the notch filter into the sensor module prevents interference from these frequencies before it reaches the user's application.
Engineers no longer need to build and execute an external notch filter because it is already included within the sensor module. This function eliminates the need for external filters, which increases system dependability, efficiency, and cost-effectiveness.
Benefits of the Integrated 50/60 Hz Notch Filter include:
- Before noise from the power grid and AC equipment reaches the sensor element, eliminate it.
- Utilize an integrated approach to streamline product design.
- Reducing the need to create and/or deploy an external notch filter will speed up time to market.
- Reduced total system cost because an external notch filter is not needed.
Pressure Switch
A mechanical or electronic mechanism known as a pressure switch is triggered when a predetermined pressure threshold or set point is achieved. If this threshold is reached, these failsafe reaction parts give the system instructions on what to do.
Types of pressure switches
Fixed Pressure Switches
As the name suggests, fixed pressure switches have predetermined pressure thresholds that the pressure switch manufacturer cannot change. The pressure switch is delivered preconfigured to the device manufacturer, who cannot alter its settings. Examples of medical equipment with fixed pressure switches are ventilators and similar devices.
Variable Pressure Switches
Variable pressure switches allow the threshold value to be set dynamically in the field or by the device manufacturer. If the device manufacturer is in charge, they choose specific resistor pairs to manage the voltage input that establishes the threshold when they design their product. The threshold value is set after the product is built and cannot be altered.
When it is possible to set the threshold in the field, a mechanical knob or switch, or software is usually used to accomplish this. In this case, the pressure switch is typically not used as a safety precaution.
A typical example is air filters, where the threshold value must be modified to account for any head loss in the flow stream, depending on how the system is implemented.
Superior's pressure switch toggles between states based on whether the measured pressure is above or below a predetermined level. In addition to providing more straightforward on/off system feedback, this can be utilized as a quick response failsafe feature in the event of overpressure.
On the other hand, the Superior Sensor pressure switch has three ways of determining threshold pressure, one fixed and the other two adjustable.
- Fixed mode: Superior Sensor Technology establishes the cutoff point and gives the device manufacturer the configured, "ready for use" sensor with an integrated pressure switch.
- Variable mode 1: The manufacturer can configure and set the appropriate thresholds when manufacturing a device.
- Variable mode 2: Software can configure pressure thresholds in the field, allowing the pressure switch to be "tuned" to the specific use case after the product is manufactured.
Benefits of Superior’s Integrated Pressure Switch include:
- Three operating modes for flexibility
- Reduced system costs because an external pressure switch is no longer required.
reduced PCB footprint overall
- Remove external components to increase the dependability of the product.
- Reduce system heat and power usage.
- Make product design simpler and accelerate time to market